

<template>
  <div>
    <div class="todo-footer">
      <label>
        <input type="checkbox" v-model="allCompleteCount" />
      </label>
      <span>
        <span>已完成{{ checkedNum }}</span> / 全部{{ todos.length }}
      </span>
      <button  @click="killComplete" class="btn btn-danger">清除已完成任务</button>
    </div>
  </div>
</template>

<script>
export default {
  name: "Footer",
  props: ["todos", "allComplete","killComplete"],
  computed: {
    allCompleteCount: {
      get() {
        // every()方法根据数组中的每个元素是否都传递在回调函数中给出的条件返回true或false。
        return this.todos.every((item) => item.done === true)&&this.todos.length!==0 
        // return "dsadasdasdas"
      },
      set(value) {
        console.log(value);
        this.allComplete(value);
      },
    },
    checkedNum() {
      return this.todos.reduce((p, c) => (c.done ? p + 1 : p), 0);
    },
  },
};
</script>

<style scoped>
/*footer*/
.todo-footer {
  height: 40px;
  line-height: 40px;
  padding-left: 6px;
  margin-top: 5px;
}

.todo-footer label {
  display: inline-block;
  margin-right: 20px;
  cursor: pointer;
}

.todo-footer label input {
  position: relative;
  top: -1px;
  vertical-align: middle;
  margin-right: 5px;
}

.todo-footer button {
  float: right;
  margin-top: 5px;
}
</style>